Improvement in hand screw-clamps



UNITED STATES PATMW.

HERMANN SGHM'IDT, OF NEW YORK, N. Y.

IMPROVEMENT IN HAND SCREWCLAMPS.

Specification forming part of Letters Patent No. 57,195, dated August 14, 1866.

To all 'whom t may concern:

Be it known that I, HERMANN SCHMIDT, of the city, county, and State or New York, have invented a new and Improved (larpenters Clamp; and I do hereby declare that the following is a full, clear, and exact description thereof', which will enable others skilled in the art to make and use the same, reference being had to the accompanying drawings, forming part of this specification, in which- Figure l represents a sectional side eleva.- tion of this invention. Fig. 2 is a horizontal section of the same, the line x x, Fig. 1, indicating the plane of section.

Similailetters of reference indicate like parts.

rlhis invention consists in a carpenters clamp, which is provided with movable nuts in such a manner that by releasing the nuts from the screws the two jaws of the clamp can be moved freely in either direction and adjusted at the desired distance apart without loss of time.

A A represent the two jaws of a carpenters clamp. These jaws are made of wood or any other suitable material, in the ordinary form or shape, and they are adjusted and compressed by means of two screws, B B. These screws are, by preference, made of iron, and the screw B is so arranged that it can turn in the jaw A, but is not allowed to move longitudinally in its socket in said jaw, while its shank passes freely through the jaw A. The screw B turns in a socket in the jaw A', but it passes freely through the jaw B.

The nuts O C of the screws B B are formed by semicircular cavities in the ends of springlevers a a', which are secured to the sides of the jaws A A', as clearly shown in the drawings; or, instead of arranging the nuts in spring-levers, they mightbe arranged in slides, or otherwise made movable, so that the same can be readily thrown in and out of gear with the screws B B.

If the nuts C C are'thrown out of gear with said screws the two jaws can be steadily moved toward or from each other, and they can be almostinstantaneously adjusted to any desired distance, whereas, with carpenters clamps ot' the ordinary construction, the operation of adjusting the jaws must be effected by turning the screws in the proper direction, which causes much loss of time.

By making the nuts movable I am enabled to set my clamp for thin or thick pieces at any moment, and the number of clamps required in a shop can be materially' reduced,

because with the present clamp it is found necessary to have a large number of clamps, so that the clamps generally used for certain articles can remain unchanged, and the time of resetting the clamps is saved.

My clamp can be adjusted toany article without loss of time, and by being enabled to reduce the number of clamps required for a shop the .higher price of my clamp is compensated.

The screws of my clamp are made of iron, which gives another great advantage-viz., the screws can be made thinner, and consequently the jaws can be compressed with more power than with ordinary clamps, the screws of which are made of wood and of considerable diameter. 

